Rotary drive device



May 1, 1945.

E. J. REGAN ROTARY DRIVE DEVICE Filed March 3, 1943 FIGB.

FIG.2.

IN V EN TOR.

Edmund J. Regan, Bloomfield'yl'slftt' assi Federal Telephone & RadioCorporation, New York, N. Y., a corporation of Delaware ApplicationMarch 3, 1943, Serial No. 477,849

2 Claims.

This inventionrelates to improvements in rotary drive devices and isparticularly directed to v a construction including a drive wheel havingan improved friction tir arrangement. It is especially adapted for usein apparatus in which the drive wheel engages a relatively flat rotatingsurface such as a disk or cone, and is desirably provided with arelatively narrow drive surface.

In drives of this type the drive surface tends to wear down, therebybroadening the drive surface and reducing the effective diameter of thewheel. An object of th invention is to provide an arrangement wherebythe narrow drive surface of the tire may be readily renewed when worn.This is in general accomplished by employing a drive ring or tire offriction material mounted in an annular channel on the rim, the ring andchannel beingprovided with cooperating surfaces arranged to hold thering in a plurality of positions each with a different portion of thering exposed in driving position. Such exposed portions of the ring areshaped in the form of ridges to provide the desired-narrow contact.

A construction of this type is conveniently provided by employing a ringthat is substantially square in cross-section, and seating it in a V-shaped channel in the rotary drive member. With this arrangement eachangle between fiat faces of the ring forms a narrow drive ridge when theoppositeangleis. seated in the channel. By twisting the ring any ridgemay be located in driving position and will be held firmly in that ratusembodying the invention, with parts broken away;

Fig. 2 is a side elevation of the drive wheel 7 shown in Fig. 1 withparts broken away, and

Fig; 3 is a diagrammatic view illustrating a method of forming the drivering.

In the specific form illustrated the drive wheel i0 is in the form of adisk mounted on shaft II and provided with a V-shaped annular channel orgroove I2 with sides l3 inclined to each other at an angle ofsubstantially 90. The drive ring 14 is square in cross-section and isproportioned so that one of its edges or ridges IE will projectsubstantially beyond the wheel l0 while the opposite sides l6 are heldsnugly against the sides l3 of channel l2 by contraction of the ring.

A cone H on shaft I8 is engaged by the narrow ridge l5 of ring I4, andshaft II is parallel to the continuous element of the surface of conel1, so that the disk l0 may be shifted along the cone surface to varythe effective drive speed in the usual manner.

Ring l4 may conveniently be formed from a cylinder 20 of suitablematerial by making successive radial cuts along dotted lines 2|.

The ring I 4 is slightly smallerin diameter than disk [0' and isstretched sufficiently to permit the operator to slip it over theoutside of the disk and to twist it into position with one angle IS inregister with the bottom of channel l2, the ring being seated firmly inthe channel when released.

To provide a fresh driving ridge I5 when the position by the engagementof the ring faces opposite to such ridge with the side walls of thechannel.

The ring is advantageously constructed of resilient material such asnatural or synthetic rubher or rubber substitutes, and in this form issufficiently resilient to facilitate location, adjustment and removal bystretching the ring to a diameter greater than that of thechannel, thering being proportioned so that when it is released it will fit tightlyagainst the channel walls, thereby assuring freedom from circumferentialslippage.

Rings suitable for this purpose may be conveniently formed by successiveradial cuts through a cylinder of friction material suchas ridgeformerly in use has become worn it is necessary only to twist the ring Min channel 12 until another ridge l5 extends outwardly in driveposition, with the opposite ridge located at the bottom of said channel.

While the wheel III has been referred to as a drive wheel it will beunderstood that either the wheel or the cooperating drive element suchas conev I! may be the driving member.

While resilient material is preferably employed for constructing ring HIand permits the positioning and shifting of the ring in channel l2without requiring any movement or removal of the channel walls, thisdisclosure is intended to be illustrative rather than restrictive. Othermodifications and variations in the described natural or syntheticrubber or rubber substitute.

Other objects and advantages will appear from the following descriptionconsidered in connecconstruction may be made without departing from theinvention as set forth in the claims.

What is claimed is: 1. A rotary drive device comprising a rotatabledrive member provided with a peripheral V- shaped channel the sideswhereof converge at an angle of substantially to one another from was:

the periphery of the drive member toward the interior thereof, and adrive tire seated in said channel, said drive tire being formed as an.

annulus having a substantially square cross section, with the innerperipheral edge thereof lying in the bottom of said channel, the outerperipheral edge of said annulus projecting beyond the peripheryofsaiddrive member and substantially one-half of the peripheral surfaceof said annulus engaging the sides of said channel, said tire being ofresilient material whereby the tire may be turned in the channel withoutremoval therefrom to have difierent edges of the tire project beyond theperiphery of the drive member, and

to assume upon said turning one of four predetermined angularpositions,whereby the drive surface of said tire is limited to a substantiallycurvilinear configuration of minimum width.

2. Rotary drive device according to claim 1, of the type having tworotary members, also including a, cooperating driven element having asurface extending longitudinally substantially in a direction normal tothe aXis of said drive member, and engaged by the projecting edge ofsaid drive tire, whereby the contact between said drive tire and saiddriven element is confined to a relatively narrow curvilinear area.

EDMUND J. REGAN.

